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FiReaNGeL writes to tell us that recent observation of slime mold could eventually lead the way to improved tech like better computer and communications networks. "This revelation comes after a team of Japanese and British researchers observed that the slime mold connected itself to scattered food sources in a design that was nearly identical to Tokyo's rail system. Atsushi Tero from Hokkaido University in Japan, along with colleagues elsewhere in Japan and the United Kingdom, placed oat flakes on a wet surface in locations that corresponded to the cities surrounding Tokyo, and allowed the Physarum polycephalum mold to grow outwards from the center. They watched the slime mold self-organize, spread out, and form a network that was comparable in efficiency, reliability, and cost to the real-world infrastructure of Tokyo's train network."

If this is the type of discussion that usually occurs at this particular web-sight, then I'm through here.

No! Anonymous Coward please don't go. Whatever will happen to this site without your inane and, often useless remarks. Where would we be without your constant trolling presence and incendiary flamebait one liners? Slashdot would surely fail without you whoring Karma away from logged in users since everyone's score would get so high that the mod level would have to approach 11!

They're pretty excited that their teams of engineers have built a rail system, that a petri dish with slime mold and oats could design in 24 hours.

On the other hand, I compared it to Kanto rail [slashdot.org] map, and while there are similarities, there are many differences too. I'm pretty sure a 2 year old can drawn the Tokyo subway map [umka.org]. It all looks like squiggles to me.:)

No, the people who designed the tokyo metro layout [mkc-properties.com] on the other hand, were most definitely high on something.

"Let's design an extremely interconnected subway system, except that in order to get across downtown you need to change lines 3 times including once to a completely different rail system. Some areas of downtown will have a train station every half block, wheras others will be mostly empty. To balance out that inconvinience, lets make all the trains run on time down to about 3 seconds, have all the

And in a surprising, yet possibly related discovery, by Austrian and American scientists, Japanese civil engineers were found growing around the edges of a particularly damp bathroom. The research was funded by the MBTA, with a grant from the Department of Homeland Security.

Tokyo's subway map has always reminded me of Japanese scat videos. Maybe they were high on that? Anyway, there is plenty of slime and mold in our datacenter. No better technology though, so this theory is busted.

Wake me up when it can complete and environmental impact assessment, defeat a coalition of concerned propertyholders suing because they don't want your "electrosmog" causing cancer, defeat a slimy local developer who really wants a route changed to improve the value of his land holdings, and then cajole the low-bidding contractor into actually building the network properly....

I am, of course, mostly joking, natural systems(ants are the other one that gets mentioned a lot) have developed some quite efficient approaches to various problems. If a problem can be solved by a large number of rounds of iterative adjustment, evolution has probably solved it good and hard somewhere. That said, though, it would be a mistake to overestimate the value of having an efficient solution on your drawing board. You cannot build an efficient system without one; but it is very easy to build a downright pathological system even with one.

Wake me up when it can complete and environmental impact assessment, defeat a coalition of concerned propertyholders suing because they don't want your "electrosmog" causing cancer, defeat a slimy local developer who really wants a route changed to improve the value of his land holdings, and then cajole the low-bidding contractor into actually building the network properly....

I would imagine that if the slime mold were forced to deal with such problems and it was large enough to do so, it would just eat th

The Wikipedia entry [wikipedia.org] for the slime mold species in question indicates that the organism actually does have some sort of primitive intelligence - it could, for example, solve mazes, and learn the pattern of a regularly reoccurring period of cold conditions (reacting appropriately). I see the stuff growing in my garden now and then... the fact that a patch of slime exhibits intelligent behavior is, I don't know, kind of weird.

The Wikipedia entry [wikipedia.org] for the slime mold species in question indicates that the organism actually does have some sort of primitive intelligence - it could, for example, solve mazes, and learn the pattern of a regularly reoccurring period of cold conditions (reacting appropriately). I see the stuff growing in my garden now and then... the fact that a patch of slime exhibits intelligent behavior is, I don't know, kind of weird.

One way of having fault-tolerant memory is to leave a chemical trail behind you. Then you don't need to expend energy maintaining a brain, memory and senses. It works for ants and snails, so a slime mold wouldn't have too much problem.

You only need to mark three things - "there is nothing worth eating here", "there is something worth eating here", or "this area is unexplored". That would only require two chemical markers; one for the "nothing to see here, move along" state and "here be nibbles" state. The m

There's a link in the references section about slime mould solving and optimising a maze route. The thing I find fascinating is they exhibit animal, plant and fungi like behaviour. Some species when it's time to reproduce gather themselves from the flat mould structure into a worm like structure, climb to the highest nearby point where they convert to a plant like structure with roots, stalk and a "flower" containing their spores.

Perhaps the existance of networks of single celled organisims is why multic

Looked at another way, perhaps we are a sophisticated network of single celled organisims.

We and every other complex creature are individuals in a symbiotic relationship with a variety of other organisms of varying complexity and running all the way down to single cells. That's not quite the same thing.

the proper conclusion is that japanese transportation engineers are no smarter than slime molds

Or indeed soap, which is also able to perform similar optimization tasks: take two pieces of perspex and join them together using bolts arranged in the pattern of your major destinations with a gap of around 1-2cm between them. Dip in a strong soap/water mixture and remove carefully. You should find a series of large bubbles have formed, with edges running between the bolts. Surface tension will probably have resulted in those edges being an optimal or close to optimal solution to the problem of joining them together with the most efficient network. Repeat several times, take the most common result.

Simple energy reduction problems like this aren't a useful test of anything. There are plenty of natural processes that don't involve intelligence that are more than capable of solving them.

I would guess not, since finding a "good" solution to TSP isn't hard at all, and nature usually doesn't bother expending 100x the resources to find the single "optimal" solution (which is practically meaningless anyways since the natural world is so dynamic. Has nature evolved the "optimal" human? If so, who is it?)

In college 1 of my professors told us a story...
A complex built several large buildings all on the same block.
They didn't install any sidewalks or walkways just grass.
They waited 1 year and looked at the grass.
They built sidewalks wherever there was a path in the grass.
The bigger the path the bigger the sidewalk.
I thought it was an interesting idea.
So many times I look back and try to wonder what the engineer/designer was thinking.

They waited 1 year and looked at the grass. They built sidewalks wherever there was a path in the grass.

I saw this phenomenon as well when I was at USF and ODU back in the '80s.

In a similar theme, I worked prep at Pizza Hut in high school and early college years and was told that Pizza Hut didn't do much research on site location, but simply put stores near McDonalds, as they did extensive research. Don't know if it's true, but there always seems to be a Pizza Hut near a McDonalds...

In a similar theme, I worked prep at Pizza Hut in high school and early college years and was told that Pizza Hut didn't do much research on site location, but simply put stores near McDonalds, as they did extensive research. Don't know if it's true, but there always seems to be a Pizza Hut near a McDonalds...

I'm sure there was some truth to the story, though "didn't do much research" was probably more like "looked at where the competition was as a starting point, then did their research from there".

It is very common to see fast-food or retail businesses clustered together for that very reason, and the more businesses there are the more people will be drawn to eat at that area, etc. Even if there is more "perceived competition" from other restaurants, the greater number of people overall will drive up business (

This is story about Tomá Baas town, Zlín. And designer did not wait year, only through winter (to see paths in snow).

I think designer though obvious: People are bound to figure out thier shortcuts and stick to them.

You can see this all over the place: is there is sharp corner somewhere, people will not follow it and tip of L will be eventually muddy, grassless ground. It is not so huge step to say "what about building sidewalk on this spot too?"

The problem is of course that sometimes you *want* a large grassy area.

My university had a central area called the "bowl" which had a single sidewalk going down the middle, and several footpaths worn through it where people took shortcuts. However, since that area was used for sports and recreation it would have cut down on the usefulness to pave the shortcuts.

It was probably true at one of them once, and if you're building a new campus today it's not a bad approach, but it's not clear where or when it actually originated.

And if you've been around Frank Lloyd Wright buildings much, you'll hear lots of stories about how they leak unless you're really aggressive about maintenance, and if you're over about 5'6"" (167cm), you'll rapidly notice that the dude was short and didn't mind forcing taller people to duck in buildings he designed...

It was probably true at one of them once, and if you're building a new campus today it's not a bad approach, but it's not clear where or when it actually originated.

When I was in boarding school in the late 70s, I was taking a well-worn diagonal short cut across a quad to my dorm when I bumped into the Rector (Principal) who chewed me out for not walking on the paths. When I went back a few years later (after said Rector had retired) I noticed that the path I used had been paved. So they may all tell that story because they all actually do it;-)

I thought for a second we might finally have a really good way to model the complex, ever-deepening relationship that's grown up between North American politicians and their corporate masters. Then I realized there's some things even a slime mold won't do.

Take two surfaces (overlapping, horizontally ) (cardboard will suffice, and place straws through them (verically)where your destinations are. Submerge it in soap/water solution. Then slowly pull it out and the surface tension will find the most efficient routes between the straws.

I assume the mold paths solution simply "converged" to the most efficient way of carrying the nutrients between the nodes. As it was mentioned here, soap bubbles will also "find" the shortest paths, as will the mold's "brute force" approach (broad spread, then coalesce to the most efficient ones).

But the natural solutions would not take into account the human distribution and convenience, as each node (apart from the big central oat flake) have the same appeal to the mold - and possibly the ones closest to the borders have less appeal (or more "cost"). Same goes for the surface tension solution (soap).

What if the human factor shifts the "weight" of some nodes and paths? For example, there might be very few people needing to go from node A to B, but many needing to go from A to C, so although a "natural" solution would only take the distances and positions into account, a "human" solution would want to favor the trip from A to C even if that meant making the A-B trip worse.

So if the mold solution is really very similar to the real rail system, then either Japanese commuters are amazingly "natural" in regards to where they live, where they work, and demographic distribution, or the Japanese railroad engineers missed the human factor when designing the grid. The first possibility is somehow beautiful and creepy at the same time.

So if the mold solution is really very similar to the real rail system, then either Japanese commuters are amazingly "natural" in regards to where they live, where they work, and demographic distribution, or the Japanese railroad engineers missed the human factor when designing the grid. The first possibility is somehow beautiful and creepy at the same time.

That is an interesting question. As a US engineer working with Japanese engineers, I am constantly comparing things they do to how we do, and wondering where general differences are and how they came about.

Very interesting. Like the underlining rules that form different fractals, these political/social differences shape different maps.

There could then be at least three "drives" competing to shape the grid: "uniformity" (theoretical ideal mold global solution, unaware of traffic needs), "traffic shaped" (overall, prioritize the majority, screw the few who needs odd itineraries), "incremental" (each line is negotiated as an isolated problem/cost, overall final result may be unoptimized) - besides the obvious "e

I guess you can manipulate the "world" of mold or soap bubbles so it will resemble the modeled scenario more. Certain spots more tasty & nutritious or the grid of points for soap with changed proportions, so that the more important hubs will be closer. Or relying on height to manipulate "strength" of each point.

It's a little sad that somebody, in pursuit of an audience, had to angle the story towards "we could be using mold to make design decisions." Your mass transit planners are not going to call in a consultant with a suitcase full of mold, obviously. The paths chosen for rail have so many political factors that the "most efficient" model has little relevance.

But just stop thinking of utility for a moment. Look at those pictures of the mold growing to reach all points and form little roads between them. That is fantastic! "Because you could then plan light rail and freight logistics and--" STOP! No, don't jump on to the practical applications yet. Take a moment to think about that simple little organism doing that complicated thing and how cool that is. Those pictures are breathtaking.

And after that, maybe try to write a matching algorithm to see if you can predict which paths will form by the slime. And then see if that algorithm offers something that the human-designed ones don't have already. And then maybe integrate and devise new algorithms based on what was learned. And then see what practical applications there are for these algorithms. This is what the scientists and engineers will actually end up doing if it is possible. Can we stop acting like bored little brats that every scientific observation isn't immediately useful?

Ironically the wheel is one of the few things nature didn't invent first. There are beasties with magnets in their heads, some with electrical generators in their muscles, sophisticated echolocation etc. etc.. A wheel and axle may be beyond Mother Nature's reach, barring some amazing fluke.

Still, reinventing the wheel isn't always such a bad thing; the first solution is rarely the optimal one.

Perhaps not quite. There are beetles forming spherical "boulders" of organic matter, that's quite close to wheel conceptually. Spherical plants moved by wind. And you can find even closer analogues in microorganisms...

The main problem with evolving large scale "proper" wheel, I guess, is of intermediate structures; apparently they were worse for survival then the alternatives.

So now only to find an organism which likes to visit every node on the map, and yet tries to omit already visited spots. A colony-like species preferably, to have large number of individual for statistical analysis...

We studied something like this in my social computing university class, only it was about slime mold "solving" a maze. I never understood why that (or this) was at all interesting; the growth of the slime mold is just a brute force search for food. What you end up with is a minimum spanning tree between the food "nodes." Meh.

It's useful because it's an extremely parallel algorithm; I believe it will execute in around O(log n) time steps with n nodes, making it a member of the class of fastest known algorith